Re: Why wasn't I told about logbitp?!

> From: Ken Tilton <kennytil...@[EMAIL PROTECTED]
>
> I just think my damn compiler has an obligation to tell me when I
> am reinventing the damn wheel!

There's a Web site that recognizes sequences of integers, such as
fibonacci numbers or prime numbers etc. You give it the first
several elements of a sequence and it tells you any sequences it
knows that starts with that initial segment.

There's anotehr Web site that recognizes real numbers, such as pi
or sqrt(2). You give it an approximate value and it shows you all
values it knows about which are similar enough to what you gave.

(Sorry, I didn't bookmark the URLs for them.)

Maybe you would like a Web site that recognizes functions. You feed
it a function definition, and it tries various parameters into it
and compares the results with the results known functions for the
same parameters until it figures out whether there is any function
that matches your function for enough inputs to give high
confidence it's the same function. It then compares your function
definition with the definition of the standard function to try to
prove they are mathematically equivalent or generate a
counterexample.

> I bet Lispworks does! Or SBCL for sure, those yobbos are solving
> im****tant problems like that all the time!! But Franz? Noooooooo!

Maybe you can interface one of those to the Web so that anyone in
the world can submit a function to compare with known functions?

> I found logbitp on the verge of only the second reinvention,

I found logbitp in CLtL1, in the section on "Logical Operations
on Numbers" (pages 220-225). Note the key phrase on page 221:
"This method of using integers to represent bit-vectors ..."
That's an example of an intentional data type,
internally integers but intentionally bit-vectors.
(Actually at the machine level it's the other way around!
 RAM has nothing but octets of bits. It's the CPU that has
 some instructions that interpret octets of bits as integers,
 and other instructions that interpret those same octets of
 bits as device control codes, and other instructions that
 interpret those same octets of bits as floating point values,
 and other instructions that treat each octet as two BCD digits,
 and other instructions that really do treat octets as bit-vectors.)